A tale of two fusion proteins: understanding the metastability of human respiratory syncytial virus and metapneumovirus and implications for rational design of uncleaved prefusion-closed trimers

Respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) cause human respiratory diseases and are major targets for vaccine development. In this study, we designed uncleaved prefusion-closed (UFC) trimers for the fusion (F) proteins of both viruses by examining mutations critical to F metastability. For RSV, we assessed four previous prefusion F designs, including the first and second generations of DS-Cav1, SC-TM, and 847A. We then identified key mutations that can maintain prefusion F in a native-like, closed trimeric form (up to 76%) without introducing any interprotomer disulfide bond. For hMPV, we developed a stable UFC trimer with a truncated F2-F1 linkage and an interprotomer disulfide bond. Tens of UFC constructs were characterized by negative-stain electron microscopy (nsEM), x-ray crystallography (11 RSV-F and one hMPV-F structures), and antigenic profiling. Using an optimized RSV-F UFC trimer as bait, we identified three potent RSV neutralizing antibodies (NAbs) from a phage-displayed human antibody library, with a public NAb lineage targeting sites Ø and V and two cross-pneumovirus NAbs recognizing site III. In mouse immunization, rationally designed RSV-F and hMPV-F UFC trimers induced robust antibody responses with high neutralizing titers. Our study provides a foundation for future prefusion F-based RSV and hMPV vaccine development.

Single-Component Multilayered Self-Assembling Protein Nanoparticles Displaying Extracellular Domains of Matrix Protein 2 as a Pan-influenza A Vaccine

The development of a cross-protective pan-influenza A vaccine remains a significant challenge. In this study, we designed and evaluated single-component self-assembling protein nanoparticles (SApNPs) presenting the conserved extracellular domain of matrix protein 2 (M2e) as vaccine candidates against influenza A viruses. The SApNP-based vaccine strategy was first validated for human M2e (hM2e) and then applied to tandem repeats of M2e from human, avian, and swine hosts (M2ex3). Vaccination with M2ex3 displayed on SApNPs demonstrated higher survival rates and less weight loss compared to the soluble M2ex3 antigen against the lethal challenges of H1N1 and H3N2 in mice. M2ex3 I3-01v9a SApNPs formulated with a squalene-based adjuvant were retained in the lymph node follicles over 8 weeks and induced long-lived germinal center reactions. Notably, a single low dose of M2ex3 I3-01v9a SApNP formulated with a potent adjuvant, either a Toll-like receptor 9 (TLR9) agonist or a stimulator of interferon genes (STING) agonist, conferred 90% protection against a lethal H1N1 challenge in mice. With the ability to induce robust and durable M2e-specific functional antibody and T cell responses, the M2ex3-presenting I3-01v9a SApNP provides a promising pan-influenza A vaccine candidate.

Views and experiences of healthcare practitioners supporting people with COPD who have used activity monitors: "More than just steps"

INTRODUCTION

Activity monitors (apps and wearables) are increasingly used by the general population, including people with Chronic Obstructive Pulmonary Disease (COPD). There is potential for activity monitors to support increases in physical activity for people with COPD and healthcare practitioners (HCPs) are likely to be key in supporting their use, but little is currently known about HCPs' views or experiences. This qualitative research aimed to explore HCPs' views and experiences of supporting people with COPD who have used activity monitors.

METHODS

Seventeen semi-structured telephone or online interviews were conducted with HCPs between September 2020 and May 2021. HCPs included two nurses, an occupational therapist, a physician, and 13 physiotherapists. Participants were recruited via social media advertisements. They all had experience of supporting people with COPD who had used activity monitors. Interviews were analysed using reflexive thematic analysis.

FINDINGS

Four themes were developed highlighting the challenges and benefits of HCPs supporting patients with using activity monitors and utilising patient-collected activity data; 1) Skills and experience are needed to increase accessibility and engagement, 2) Objectively monitored physical activity can support exercise prescription, 3) Applications of activity monitors vary across different settings, and 4) Support is needed for future use of activity monitors.

DISCUSSION

HCPs recognised the potential for activity monitors to impact patients' ability to self-manage their COPD. However, there is a lack of guidance and information to support integration within practice. Future research is needed to co-develop information and guidelines for people with COPD and HCPs.

Durable Response after Repeat Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in a Patient with Extensive Mucinous Adenocarcinoma of the Appendix

Mucinous adenocarcinoma of the appendix is a rare form of lower gastrointestinal (GI) tract cancer. These cancers have a high tendency to progress towards peritoneal metastasis and their response to systemic treatment is typically low. Together, cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have become an established form of therapy used to prolong the survival of patients with this disease. Repeat CRS and HIPEC have been shown to be feasible in selected patients with GI peritoneal carcinomatosis (PC), among which those with appendix cancer receive the greatest benefit. The peritoneal cancer index (PCI) and completeness of cytoreduction have been shown to be important predictors of outcomes. However, repeat cytoreduction in patients with a high-volume peritoneal tumor burden (peritoneal cancer index (PCI) > 30) is not typically performed due to concerns regarding morbidity and mortality. Herein, we describe a case of repeat CRS and HIPEC for extensive appendiceal mucinous peritoneal carcinomatosis after initial incomplete cytoreduction and durable remission of 28 months without adjuvant chemotherapy. In appendiceal mucinous cancers, repeat CRS can achieve a durable response despite an initial failed CRS and high-volume disease.

Early Adoption of Checkpoint Inhibitors in Patients with Metastatic Gastric Adenocarcinoma-A Case Series of Non-Operative Long-Term Survivors

Checkpoint inhibitor (CPI) therapy has only recently been introduced in the first-line treatment of advanced gastric cancer. However, later line monotherapy CPI efficacy in a subset of patients was presented about four years prior. Here, we present three cases of advanced gastric adenocarcinoma cancers treated with CPI in early lines years prior to the availability of randomized first line data. All three patients remain in remission without gastrectomy, with the median time from initial diagnosis of approximately 52 months. With long-term follow-up of more than four years, we present a proof of concept that, with early integration of CPI therapy, highly durable responses are possible even in the absence of surgery in patients with advanced gastric and gastroesophageal junction cancers.

Seeded droplet microfluidic system for small molecule crystallization

A microfluidic approach to seeded crystallization has been demonstrated using abacavir hemisulfate, a nucleoside analog reverse transcriptase inhibitor, in droplet reactors to control polymorphism and produce particles with a low particle size distribution. Two techniques are introduced: (1) the first technique involves an emulsion system consisting of a dispersed phase solvent and a continuous phase, which holds slight solubility of the dispersed phase solvent. The dispersed phase contains both a dissolved active pharmaceutical ingredient (API) and seeds of the desired polymorph. While the continuous phase enables solvent extraction, the negligible solubility of the API allows for growth of seeds inside droplets via extraction and subsequent API saturation. This technique demonstrates the ability to crystallize the API in spherical agglomerates via slow extraction of droplets. (2) The second technique utilizes a combined dispersed phase by joining in-flow a seed suspension stream with a supersaturated active pharmaceutical ingredient (API) stream. The combined dispersed phase is emulsified in a continuous phase for which the dispersed phase solvent and the API are both insoluble - droplets are incubated at temperatures below their saturation limit to induce crystal growth. Decreasing the concentration of seeds in its input stream resulted in a decreased number of crystals per droplet, increase in crystal size, and decrease in PSD. Temperature cycling was utilized as a proof of concept to demonstrate the ability to reduce the number of seeds per droplet where the optimal goal is to obtain a single seed per droplet for all droplets. Utilizing this approach in conjunction with the ability to produce monodispersed droplet reactors allows for enhanced control of particle size distribution (PSD) by precisely controlling the available mass for each individual seed crystal. The development of this technique as a proof-of-concept for crystallization can be expanded to manufacturing scales in a continuous manner using parallelized droplet generators and flow reactors to precisely control the temperature and crystal growth kinetics of individual droplets.

From Paper to Practice: The Views of Occupational Therapists on the Impact of the National Service Framework for Older People on Practice

Philp (2003) outlined the fundamental role that occupational therapists could have in implementing the National Service Framework (NSF) for Older People and reforming services for older people (Department of Health 2001). A research project was undertaken, which aimed to investigate the views of occupational therapists about the implementation of the policy in order to identify the key areas and issues that have had an impact on practice. The research design was qualitative and took the form of focus groups.

The focus group data were analysed using a long-table analysis method (Krueger and Casey 2000), which identified five key themes: a raised profile of older people's services, a changing delivery of services, a revisiting of occupational therapy core skills, assessment and resource allocation. The emerging themes suggested that the NSF for Older People has had an impact on the practice of the occupational therapists involved in the focus groups.

Superiority of Deformable Image Co-registration in the Integration of Diagnostic Positron Emission Tomography-Computed Tomography to the Radiotherapy Treatment Planning Pathway for Oesophageal Carcinoma

AIMS

To investigate the use of image co-registration in incorporating diagnostic positron emission tomography-computed tomography (PET-CT) directly into the radiotherapy treatment planning pathway, and to describe the pattern of local recurrence relative to the PET-avid volume.

MATERIALS AND METHODS

Fourteen patients were retrospectively identified, six of whom had local recurrence. The accuracy of deformable image registration (DIR) and rigid registration of the diagnostic PET-CT and recurrence CT, to the planning CT, were quantitatively assessed by comparing co-registration of oesophagus, trachea and aorta contours. DIR was used to examine the correlation between PET-avid volumes, dosimetry and site of recurrence.

RESULTS

Positional metrics including the dice similarity coefficient (DSC) and conformity index (CI), showed DIR to be superior to rigid registration in the co-registration of diagnostic and recurrence imaging to the planning CT. For diagnostic PET-CT, DIR was superior to rigid registration in the transfer of oesophagus (DSC=0.75 versus 0.65, P<0.009 and CI=0.59 versus 0.48, P<0.003), trachea (DSC=0.88 versus 0.65, P<0.004 and CI=0.78 versus 0.51, P<0.0001) and aorta structures (DSC=0.93 versus 0.86, P<0.006 and CI=0.86 versus 0.76, P<0.006). For recurrence imaging, DIR was superior to rigid registration in the transfer of trachea (DSC=0.91 versus 0.66, P<0.03 and CI=0.83 versus 0.51, P<0.02) and oesophagus structures (DSC=0.74 versus 0.51, P<0.004 and CI=0.61 versus 0.37, P<0.006) with a non-significant trend for the aorta (DSC=0.91 versus 0.75, P<0.08 and CI=0.83 versus 0.63, P<0.06) structure. A mean inclusivity index of 0.93 (range 0.79-1) showed that the relapse volume was within the planning target volume (PTVPET-CT); all relapses occurred within the high dose region.

CONCLUSION

DIR is superior to rigid registration in the co-registration of PET-CT and recurrence CT to the planning CT, and can be considered in the direct integration of PET-CT to the treatment planning process. Local recurrences occur within the PTVPET-CT, suggesting that this is a suitable target for dose-escalation strategies.

Altered Doppler flow patterns in cirrhosis patients: an overview

Doppler ultrasonography of the hepatic vasculature is an integral part of evaluating precirrhotic and cirrhotic patients. While the reversal of the portal venous flow is a well-recognized phenomenon, other flow patterns, although not as easily understood, may play an important role in assessing the disease status. This article discusses the different characteristic flow patterns observed from the portal vein, hepatic artery, and hepatic vein in patients with liver cirrhosis or related complications and procedures. Knowledge of these different flow patterns provides additional information that may reinforce the diagnosis of cirrhosis, help in staging, and offer prognostic information for determining the direction of therapy. Doppler ultrasonography is invaluable when liver transplantation is being considered and aids in the diagnosis of cirrhosis and portal hypertension.

Glucose effectiveness in nondiabetic relatives: dysglycemia and β-cell function at 10 years

AIMS

Reduced glucose effectiveness is a predictor of future glucose tolerance in individuals with a family history of type 2 diabetes. We examined retrospectively at 10 years in normoglycemic relatives of diabetic subjects (RELs) the pathophysiological role of glucose effectiveness in the development of isolated impaired fasting glucose, glucose intolerance, and acute insulin release.

METHODS

At 0 years, 19 RELs and 18 matched control subjects had glucose effectiveness (GE), insulin sensitivity, acute insulin release (AIR)IVGTT, and disposition index measured during an iv glucose tolerance test (IVGTT), using the minimal model analysis. At 0 and 10 years, oral glucose tolerance (OGTT) and AIROGTT were determined.

RESULTS

At 0 years, fasting glucose (FG) and GE were raised in RELs, but insulin sensitivity and AIROGTT were reduced (P ≤ .05) compared with controls. At 10 years, RELs developed raised fasting and 2-hour OGTT glucose. FG10y correlated significantly with FG0y and body mass index0y and negatively with √GE and 2-hour OGTT glucose10y with FG0y and negatively with AIRIVGTT0y and AIROGTT0y. Log AIROGTT10y correlated with √GE, log AIRIVGTT0y and log AIROGTT0y. Multiple regression analyses demonstrated the following: REL FG10y was predicted by combined FG0y, √GE and body mass index0y (radj(2) = 56%; P ≤ .001) and 2-hour OGTT glucose10y weakly related by FG0y,and √GE (r(adj)(2) = 25%; P = .06). Log AIROGTT10y was predicted by AIRIVGTT0y and √GE (r(adj)(2) = 46%; P ≤ .004).

CONCLUSION

In normoglycemic RELs, a relative reduction of glucose effectiveness is an important contributor over 10 years to the development of isolated impaired fasting glucose and reduced acute insulin secretion.

Does physical activity affect quality of life, disease symptoms and immune measures in patients with inflammatory bowel disease? A systematic review

Inflammatory bowel diseases (IBD) are a group of chronic, episodic inflammatory conditions of the large and small intestines. Individuals with IBD have been reported to use physical activity (PA) as a complementary therapy although the effectiveness of PA for reducing disease burden in patients with IBD is not known. The review objective is to evaluate published studies on physical activity and IBD focusing on quality of life, disease burden markers and immunological outcomes. A literature search was carried out using MEDLINE, WEB OF SCIENCE, CINHAL, and SCOPUS (to December 2008). Studies were included if they 1) were provided in English; 2) dealt with IBD in humans; 3) focused on the outcome measures of health related quality of life, clinical disease indicators or immune function; and 4) included PA as a primary intervention for IBD cases. In total, 7 studies were included in this systematic review: 5 were on PA and quality of life measures and inflammatory disease markers, and 2 on PA and immune measures. Four studies showed that PA significantly increased quality of life for IBD patients as assessed by various questionnaires. PA was also associated with decreased disease activity. There was no evidence that PA affected immune outcomes in patients with IBD. The role of PA as an adjunctive therapy for patients with IBD has not been well characterized in the literature. However, there is some evidence that PA may improve quality of life and reduce disease activity in patients with IBD.

Implementing a 48 h EWTD-compliant rota for junior doctors in the UK does not compromise patients' safety: assessor-blind pilot comparison

BACKGROUND

There are currently no field data about the effect of implementing European Working Time Directive (EWTD)-compliant rotas in a medical setting. Surveys of doctors' subjective opinions on shift work have not provided reliable objective data with which to evaluate its efficacy.

AIM

We therefore studied the effects on patient's safety and doctors' work-sleep patterns of implementing an EWTD-compliant 48 h work week in a single-blind intervention study carried out over a 12-week period at the University Hospitals Coventry & Warwickshire NHS Trust. We hypothesized that medical error rates would be reduced following the new rota.

METHODS

Nineteen junior doctors, nine studied while working an intervention schedule of <48 h per week and 10 studied while working traditional weeks of <56 h scheduled hours in medical wards. Work hours and sleep duration were recorded daily. Rate of medical errors (per 1000 patient-days), identified using an established active surveillance methodology, were compared for the Intervention and Traditional wards. Two senior physicians blinded to rota independently rated all suspected errors.

RESULTS

Average scheduled work hours were significantly lower on the intervention schedule [43.2 (SD 7.7) (range 26.0-60.0) vs. 52.4 (11.2) (30.0-77.0) h/week; P < 0.001], and there was a non-significant trend for increased total sleep time per day [7.26 (0.36) vs. 6.75 (0.40) h; P = 0.095]. During a total of 4782 patient-days involving 481 admissions, 32.7% fewer total medical errors occurred during the intervention than during the traditional rota (27.6 vs. 41.0 per 1000 patient-days, P = 0.006), including 82.6% fewer intercepted potential adverse events (1.2 vs. 6.9 per 1000 patient-days, P = 0.002) and 31.4% fewer non-intercepted potential adverse events (16.6 vs. 24.2 per 1000 patient-days, P = 0.067). Doctors reported worse educational opportunities on the intervention rota.

CONCLUSIONS

Whilst concerns remain regarding reduced educational opportunities, our study supports the hypothesis that a 48 h work week coupled with targeted efforts to improve sleep hygiene improves patient safety.

An assessment of endoscopic and concomitant management of acute variceal bleeding at a tertiary care centre

BACKGROUND

Several therapies have been demonstrated to be beneficial in the management of acute variceal bleeding (AVB). The aim of the present study was to characterize the use of these therapies at a Canadian tertiary care centre.

PATIENTS AND METHODS

A comprehensive chart review was performed to assess the management of all adult cirrhotic patients with AVB who were admitted to a university-affiliated, tertiary care centre between April 2001 and March 2004.

RESULTS

A total of 81 AVB patients were identified with a mean age of 53.7+/-13.2 years and a median model for end-stage liver disease score of 14. Endoscopy was performed within 8.2+/-7.6 h of admission. Variceal banding was performed for 87% of patients with esophageal varices, which were the most common source of bleeding (80%). Octreotide was used in 82% of patients for a mean duration of 74.3+/-35.4 h; prophylactic antibiotics were used in 25% of patients and beta-blockers were used in 24% of patients without any contraindications. Follow-up endoscopy was arranged for 46 of 71 (65%) survivors. Prophylactic antibiotic use was associated with the presence of ascites, while beta-blockers were used more often in the last year of the study.

CONCLUSIONS

There is a disconnection between the use of evidence-based recommendations and routine clinical practices in the management of AVB. Deficiencies identified include the lack of use of prophylactic antibiotics and beta-blockers, variable use of octreotide and inadequate follow-up recommendations. There is a need to identify measures to improve the process of care for patients with AVB which would ensure optimal management of these patients.

A 125Te and 23Na NMR investigation of the structure and crystallisation of sodium tellurite glasses

125Te static nuclear magnetic resonance (NMR) and 23Na and 125Te magic angle spinning (MAS) NMR have been used, in conjunction with X-ray diffraction, to examine the structure and crystallisation behaviour of glasses of composition xNa2O.(1-x)TeO2 (0.075 x 0.4). The MAS NMR 23Na spectra from the glasses are broad and featureless but shift by approximately +5 ppm with increased x, i.e. as the system becomes more ionic. The static 125Te NMR spectra show an increase in axial symmetry with increasing x, indicating a shift from predominantly [TeO4] to [TeO3] structural units. The 23Na and 125Te spectra from the crystallised samples have been fitted to obtain information on the sites in the metastable crystal phases, which are the first to form on heating and which are therefore more closely related to the glass structure than thermodynamically stable crystal phases. New sodium tellurite phases are reported, including a sodium stabilised, face centred cubic phase related to delta-TeO2; a metastable form of Na2Te4O9 containing 3 sodium and 4 tellurium sites; and a metastable form of Na2Te2O5 containing 2 sodium sites. There is evidence of oxidation of TeIV to TeVI occurring in glasses with high values of x and, at x=0.40 and 0.50 (outside the glass forming range), some sodium metatellurate (Na2TeO4) is formed at the same time as sodium metatellurite (Na2TeO3). The 125Te shift is very sensitive to environment within the sodium tellurite system, covering more than 320 ppm, with anisotropies varying from 640 to 1540 ppm. The lack of features in the 125Te spectra of the glass phases, combined with the large shift range and high but variable anisotropy, means than it is not possible to obtain a unique fit to any presumed species present. Furthermore, the chemical shift anisotropy parameters for three of the four Te sites in the Na2Te4O9 phase are found to lie outside the range used for previous simulations of glass spectra.

Population change between 1986 and 1996 in Australia: population numbers, components of change and age profiles

"This paper represents a preliminary analysis of the release of 1996 Census-based ERP [estimates of resident population] by examining regional population shifts and components of population change in Australia between 1986 and 1996.... With particular reference to Queensland, this paper also examines changes in the age profiles of regional populations over the decade to June 1996. Changes in the population structure of Queensland's growth regions are compared with those of regions experiencing population decline."

Acute exposure to a novel stressor further reduces the habituated corticosterone response to restraint in rats

The present study sought to identify dishabituation of the hypothalamic-pituitary-adrenal(HPA) axis response to different psychological stressors. Young adult male Sprague Dawley rats were exposed to five, 1 h sessions of restraint stress on five consecutive days. On the sixth day, and 2 h before additional exposure to restraint, animals were subjected to 30 min of a small (27cm square), elevated open field stressor (pedestal), which served as the dishabituating stimulus. We predicted HPA axis response dishabituation in chronically restrained rats exposed to the novel pedestal. Rats which underwent five days of restraint stress showed significantly blunted plasma corticosterone levels to restraint (habituation) as compared to restraint-nai've rats. However, rats which underwent five sessions of restraint responded with an enhanced habituation response when confronted with restraint shortly after exposure to the novel pedestal. Instead of HPA axis response dishabituation, we observed enhanced habituation. Subsequent experiments determined that a 1.25 mgkg corticosterone injection could substitute for pedestal exposure to produce enhanced restraint habituation.Combined treatment with both the glucocorticoid receptor antagonist RU40555 (30 mgkg)and the mineralocorticoid receptor antagonist RU283 18 (50 mgkg) blocked the expression of enhanced habituation after pedestal exposure. Thus, the delayed corticosterone negative feedback produced by novel stress led to enhanced expression of corticosterone response habituation.